No abstract

Background: Serum albumin is a marker of nourishment and inflammation. Although hypoalbuminemia in hemodialysis patients is reported as a risk factor for poor prognosis, few studies describe its effects on infectious diseases specifically. This study aimed to examine the relationship between the serum albumin level on admission and infection-related in-hospital death among hemodialysis patients. Methods: This was a multicenter retrospective observational study that was undertaken in Japan. We reviewed the medical records of 507 hemodialysis patients aged > 18 years, whose blood cultures were obtained based on suspicion of infectious disease, and who were managed at seven Japanese tertiary dialysis units from August 2011 to July 2013. The outcome measure was infection-related in-hospital death. Multivariate logistic regression models adjusted for age, sex, the dialysis vintage, diabetes mellitus, bacteremia, and log C-reactive protein levels were used for the statistical analysis. Results: Four hundred patients were analyzed and allocated to three groups based on their serum albumin levels: marked hypoalbuminemia (< 2.5 mg/dL), mild hypoalbuminemia (≤ 2.5-< 3.5 mg/dL), and normal albumin levels (≤ 3.5 mg/dL). The infection-related in-hospital death rates were 22.9% (n = 11), 12.5% (n = 25), and 4.6% (n = 7), respectively. The multivariate logistic regression models determined that a low serum albumin level was an independent risk factor for infection-related in-hospital death (odds ratio 0.35, 95% confidence interval 0.18-0.66). Conclusions: A low serum albumin level strongly predicts infection-related in-hospital death in hemodialysis patients hospitalized on suspicion of infection. Like those with bacteremia or diabetes mellitus, hemodialysis patients with hypoalbuminemia require careful management of their infections.

Climate change should be of special concern for the nephrologist as the kidney has a critical role in protecting the host from dehydration, but is also a favorite target of heat stress and dehydration. Here we discuss how rising temperatures and extreme heat events may affect the kidney. The most severe presentation of heat stress is heat stroke, which can result in severe electrolyte disturbance and both acute and chronic kidney disease. However, lesser levels of heat stress also have multiple effects, including exacerbating kidney disease and precipitating cardiovascular events in subjects with established kidney disease. Heat stress can also increase the risk for kidney stones, cause multiple electrolyte abnormalities, and induce both acute and chronic kidney disease. Recently there have been multiple epidemics of chronic kidney disease of uncertain etiology in various regions of the world, including Mesoamerica, Sri Lanka, India and Thailand. There is increasing evidence that climate change and heat stress may have a contributory role in these conditions, although other causes including toxins could also be involved. As climate change worsens, the nephrologist should prepare for an increase in diseases associated with heat stress and dehydration.

Hyperuricemia is common in chronic kidney disease (CKD) and may be present in 50% of patients presenting for dialysis. Hyperuricemia can be secondary to impaired glomerular filtration rate (GFR) that occurs in CKD. However, hyperuricemia can also precede the development of kidney disease and predict incident CKD. Experimental studies of hyperuricemic models have found that both soluble and crystalline uric acid can cause significant kidney damage, characterized by ischemia, tubulointerstitial fibrosis, and inflammation. However, most Mendelian randomization studies failed to demonstrate a causal relationship between uric acid and CKD, and clinical trials have had variable results. Here we suggest potential explanations for the negative clinical and genetic findings, including the role of crystalline uric acid, intracellular uric acid, and xanthine oxidase activity in uric acid-mediated kidney injury. We propose future clinical trials as well as an algorithm for treatment of hyperuricemia in patients with CKD.

Hyperuricemia predicts the development of chronic kidney disease (CKD) and metabolic complications, but whether it has a causal role has been controversial. This is especially true given the 2 recently conducted randomized controlled trials that failed to show a benefit of lowering uric acid in type 1 diabetes-associated CKD and subjects with stage 3–4 CKD. While these studies suggest that use of urate-lowering drugs in unselected patients is unlikely to slow the progression of CKD, there are subsets of subjects with CKD where reducing uric acid synthesis may be beneficial. This may be the case in patients with gout, hyperuricemia (especially associated with increased production), and urate crystalluria. Here, we discuss the evidence and propose that future clinical trials targeting these specific subgroups should be performed.